Hi Sonu, Welcome to HealthcareMagic Forum.
You haven't mentioned when was the First date of your Last Menstrual Period (LMP)? Considering your periods are regular and of 28 days duration, you have had sex during the fertile period and you will have chances of conceiving. Wait for your Next periods, if they get delayed, wait for a week and then get a Urine Pregnancy
test done using a early morning urine sample which is most ideal for detecting pregnancy. If it is Positive, get yourself examined by a Gynecologist at the earliest so that she can examine you and confirm it and take necessary steps. Avoid stress
as it is known to delay your Periods.
Good Luck, Take Care.